This invention relates to an exterior side mirror which may be mounted to a transport truck, bus or other similar vehicle, and having incorporated therein a wiper blade and operating mechanism for clearing moisture and grime from the surface of the mirror.
Drivers of commercial vehicles such as transport trucks, large motorhomes or busses or the like are required to maneuver such vehicles rearwardly in relatively confined spaces. Due to the overall length of the vehicle, the need to accurately judge the position of the vehicle in relation to stationary objects, especially as the vehicle is being backed-up, is relatively difficult since such vehicles do not normally provide a rearward view from a rear window. A clear and unobstructed rearward view from the exterior side mirrors of such vehicles by an operator is therefore paramount.
Often the view seen by the driver through a vehicles"" exterior side mirror is distorted or impaired by mud or moisture thrown up by the front wheels during travel or by raindrops or condensation covering the mirror surface during rest. In order to clear the exterior side mirrors one must often physically clean the mirror surface which generally requires that one must exit the drivers"" seat of the vehicle, leaving the vehicle unattended. This is a waste of time for the driver and is often only done when the rearview in the mirrors is virtually obliterated. Further, such cleaning is only of a temporary nature, depending on the weather.
It is, therefore, an object of this invention to provide a vehicle exterior rearview mirror having a wiper blade and operating mechanism remotely operable by the driver from inside the vehicle.
Further it is an object of this invention to provide a vehicle exterior rear-view mirror where the wiper will automatically nest in proximity to a side edge of the mirror thereby causing minimal reduction or interference with the viewing surface area of the mirror.
The exterior side mirror of the present invention has a weather-tight housing which may be secured, by suitable brackets, to prior art mounting arms found on common commercial vehicles. A wiper, in contact with the mirror surface, is operated from within the cab of the vehicle by suitable switches, the switches positioned within reach of the driver. Means for defrosting and/or washing the mirror may be provided for, as well as continuous or intermittent operation of the wiper.
The mirror housing may contain a compact 12-volt electrical motor which may have a speed reducer mechanism mounted over its output shaft. A drive arm may be fixedly mounted to the output shaft from the speed reducer mechanism on the motor so as to be rotatable at a much reduced rate from that of the motor. A linkage arm rotatably couples the drive arm to a rocker disk which is rotatably mounted to an internal mounting plate within the weather-tight housing of the mirror. Three hundred sixty degree rotation of the drive arm by operation of the electric motor imparts a back-and-forth arcuate rocking motion to the rocker disk.
A transversely mounted track is positioned within the mirror housing, for example adjacent the upper and lower transverse edges of the mirror. The track is, by way of example, tee shaped so that, when fixedly mounted to the internal mounting plate, the opposed arms are spaced from the mounting plate. An upper and lower wiper blade mounting bracket is fitted over the transverse track so as to be freely slidable thereon. The transverse track has an internal recess closely conforming the cross-sectional shape of the track. Movement of the wiper blade mounting bracket along the transverse track is enhanced by the composition of the contacting surfaces so as to reduce friction. The wiper blade mounting brackets, when positioned on their respective transverse tracks extend slightly outwardly of the outer surface of the mirror. A wiper blade is mounted to the mounting brackets for movement across and in contact with the exterior surface of the mirror.
Operation of the mirror wiper may be through a cable actuated through the back-and-forth arcuate rocking motion to the rocker disk. The operating cable is fastened to both the upper and lower wiper blade mounting bracket. Upper and lower pairs of corner sheaves are positioned in general tangential alignment with the operating cable fastening points on the wiper blade mounting brackets. As the operating cable passes over the corner sheaves they extend generally parallel to the upper and lower transversely mounted tracks. The operating cable passes outwardly around intermediate sheaves positioned adjacent to the rocker disk and then cross over the surface of the rocker disk. The rocker disk has parallel grooves on its perimeter surface to keep the operating cable separated as it crosses over this disk.
In summary, the side mirror wiper according to the present invention includes a mirror housing defining a cavity. A mirror is mounted to one side of the housing so as to define a wall of the cavity. A drive means is mounted in the housing. A crank is rotatably mounted to the drive means. The drive means rotates the crank continuously, three hundred sixty degrees in a first plane parallel to a second plane containing the mirror. A drive arm is rotatably mounted to a distal end of the crank, at a first end of the drive arm. An opposite second end of the drive arm is rotatably mounted to a rocker. The rocker is pivotally mounted on a pivot in the housing for reciprocating rocking rotation of the rocker in generally the first plane between a first position rotated towards a first side edge of the mirror and a second position rotated towards a second side edge of the mirror opposite the first side edge of the mirror. The second end of the drive arm is pivotally mounted to the rocker between the pivot and a first side of the rocker so that continuous uni-directional three hundred sixty degree rotation of the crank translates the second end of the drive arm generally linearly in a reciprocating linear translation thereby driving the rocker back-and-forth between the first and second positions.
A generally linear first elongate aperture is formed adjacent the mirror and extends between a spaced apart pair of pulleys rotatably mounted in the housing, within the cavity behind the mirror. A flexible member such as a cable frictionally engages the rocker and extends around the pulleys so as to run along the first elongate aperture. The flexible member, where it engages the rocker, is spaced both from the pivot and from the second end of the drive arm so that the rocker forms a bell crank. That is, the linear reciprocating translation of the second end of the drive arm translates the flexible member back-and-forth in a reciprocating motion generally perpendicular to the reciprocating linear motion of the second end of the drive arm so as to thereby translate back-and-forth the flexible member in the run along the first elongate aperture.
A wiper means is mounted to the flexible member through the first elongate aperture, the wiper means slidably mounted to a spaced apart pair of guides adjacent to the mirror so that the translation back-and-forth of the flexible member along the first elongate aperture correspondingly translates the wiper means back-and-forth in wiping engagement over an outer surface of the mirror between the pair of guides.
A second pair of pulleys may be rotatably mounted in the housing in the first plane at an opposite edge of mirror, that is, opposite to the first pair of pulleys. The flexible member also extends around the second pair of pulleys in an endless loop. A second elongate aperture is adjacent the opposite edge of the mirror and is generally parallel to the first elongate aperture. The second elongate aperture is parallel and adjacent to a second run of the flexible member extending between the second pair of pulleys. The wiper means is also mounted to the flexible member through the second elongate aperture.
The rocker may have a semi-circular face in the engagement with the flexible member. At least one channel may be formed in the semi-circular face. The flexible member, where the flexible member is in frictional engagement with the rocker, lies in the at least one channel under tension between a third pair of pulleys rotatably mounted in the housing. The flexible member lies along a length of the channel corresponding to a radial sector, which may be ninety degrees, of the rocker, radial relative to the pivot. The rocker may be a generally semi-circular plate. The channels may be a parallel pair of channels. The third pair of pulleys may be spaced apart from the first pair of pulleys so that the first and third pairs of pulleys define the four corners of a trapezoid. The trapezoid defined by the first and third pairs of pulleys may be a rectangle.
An axis of rotation of the crank and an axis of rotation of the rocker may be both orthogonal to the first and second planes and vertically aligned one above the other. The axis of rotation of the rocker may be vertically above the axis of rotation of the crank.
The housing may be a generally rectangular housing adapted to be mounted, by mounting means, to the side of a vehicle so as to dispose the rectangular housing vertically along its length, and wherein the elongate apertures extend substantially the entire width of the housing across the top and bottom of the housing adjacent the mirror.
The wiper means may be a rigid arm extending the length of the mirror, perpendicular to the elongate aperture, and spaced over and parallel to the outer surface of the mirror. A resilient wiper blade may be mounted to the rigid arm so as to contact the outer surface of the mirror. The guides may be a pair of tracks mounted in the housing behind the elongate apertures. The wiper means may further include a pair of posts slidably mounted on the tracks and extending through the elongate apertures, the rigid arm mounted at its ends to the posts.
The first pair of pulleys may be mounted in upper left and right corners of the housing relative to the outer surface of the mirror when viewed in front elevation. The second pair of pulleys may be mounted in lower left and right corners of the housing, again relative to the outer surface of the mirror when viewed in front elevation. The third pair of pulleys may be mounted directly below the first pair of pulleys on either side of the rocker. The pivot may be below and centered between the third pair of pulleys. The crank may be directly below the pivot. The second pair of pulleys may be below the crank.